Last lathe



April 8, 1930. E. TOPHAM LAST LATHE Filed Aug. 15, 1928 2 Sheets-Sheet 1April 8; 1930. E. TOPHAM 1,753,391

LAST LATHE Fild Aug. 15, 1928 2 Sheets-Sheet 2 Patented Apr. 8, 1930UNITED STATES PATENT emer- LAURENCE E. TOIPHAM, OF WENHAM,MASSACHUSETTS, ASSIGNOR TO UNITED SHOE MACHINERY CORPORATION, OFPATERSON, NEW JERSEY, A

JERSEY LAST LATHE Application filed August 15, 1928. Serial No. 299,690.

429,719, filed Dec. 10, 1920', now Patent #1,? 16,672; Serial No.530,214, filed Jan. 18, 1922, now Patent #1,? 13,7 92; and Serial No.284,078, filed June 9, 1928, now Patent #1,724,981.

In these applications, I have shown a width grading mechanism which canbe made to operate with a variable magnlfication factor, andinparticular with a factor which varies in any predetermined cycle, intime with the rotation of the model and last block; A practical problemdiscussed in my prior applications mentioned was that of last widthgrading from a model in such a Way that the bottom face of themodel isreproduced exactly in the last block, all the width grading being doneabove the bottom.

The width grading mechanism as hereto-.

fore constructed in copying lathes has always multiplied the modelradius, measured from the axis of rotation to the surface point then incontact with the model Wheel, by the grading factor then being utilized,or in ordinary language, the machine grades from the radius. The presentinvention contemplates grading from the diameter, as measuredperpendicularly through the model axis from the surface point in contactwith the model wheel, to the other side, with the advantage that whenanomalous grading is being done in one part of the rotation cycle, aswhen the bottom of the model is being held unchanged, the entirediameter of the last is available for magnification in the opposite partof-the rotation cycle, as on the upper side of the model, instead ofmerely the upper radius alone. The diameters of lasts, in theirfootfitting portions, vary less extremely than their radii, and thus ingrading from the diameter a magnification factor cycle can be foundwhich will be better adapted to the entire foot-fitting portion of thelast than in the case where the grading is done from Y the radius alone,since some radii of a last, for example, at the upper surface of theball portion, are often small, and a magnification,

factor which will adequately magnify the entire cross-section at suchpoints without the CORPORATION 01 NEW help of the larger radii runningto the bottom may be ill adapted to the other parts of the last Wherethe radii to the upper surface are much longer.

The invention, therefore, comprises, in its method aspect, themagnification or grading of models by, in effect, increasing theirdiameters (instead of their radii) and adding algebraically, in thework, a part of the diameter instead of a part of the radius, inbuilding up the surfaceof the work. I

' In the operation of the machine illustrated as embodying the inventioninits machine of the invention may be practised, the two radii forming adiameter are simultaneously measured, and the effect due to each istransaspect and by the aid of which the method sponding diameter in thework, so that the total diametral magnification isthe same as in gradingfrom the radius,but half of it is applied at each end of the diameter,instead of that part of the magnification due to each radius beingapplied at the end of that radius. Thus the accretion at the end of asmall radius, with a given magnification factor, can be larger thanunder the former practice, and if the oppositely extending radius is notto be magnified, it is not necessary to use such an extrememagnification factor on the short radius. In the illustrated machine theends of the two opposed radii contact withtwo model wheels respectively,and these contacts control a grading slide.

These and other features and aspects of the invention will be betterunderstood from the following description of a preferred embodiment ofthe machine aspect of the invention, by means of which the method can bepractise V In the drawings, 7

Fig. 1 is a front elevation of a last lathe embodying the invention in apreferred form and Fig. 2 is an. enlarged sectional side elevation ofthe swing frames and model Wheel carriage of the machine shown in Fig.1.

In the illustrated last lathe, the swing frame 10 is similar inconstruction to that shown in my application Serial No. 530,2l l, filedJan. 18,1922, to which reference may be made for details not hereindescribed. The center of rotation is the axis of the heavy shaft 12.

The \Vllfilllll grading fanboafrd 1-6 is pivoted at 18 on the machineframe. It contacts with a feele'r roll 20 on the end of a feeler link 22pivoted to the model wheel or grading slide 24 at 26. The link 22 isshown in neutral position, under which condition a link 28, pivoted toit,will just reach to-the pivotal center of a slotted- .segment mountedon -the model wheel carriage 33. A block as, to which the link 28 ispivotally connected, is-adjustable in the slot in the segment 32 by alink 36 which is adjustable by a handle 38 on a shaft 40 having a Wormand screw connection with a cranx arm 42 pivoted to the link-3'6. Properadjustment of the block 34 will '-therefore adjustfthe roll 29' on thefanboard 16. The segment 32 can hmoved about its pivotal center 30'hy aroll i l on an arm 46 attached to the segment, actuated by 'a cam on agear 50, which is rotated at the same speed as the model and block. Themovement oftlie-segment thus imparts a cyclic movement to the .roll 20,when the block 34 is-set oi the center 30, and thereby automaticallyeffects cyclic variation of the position of the roll 20 and consequentlyof the width grading factor, the length of the cycle corresponding tothe rotation time of the model and work. This width grading mechanismwillbe found more fully explained in my application Serial No. 429,719,filed .Dec. 10, 1929. Obviously the cam 18 can he "designed to returnthe roll 20 to its neutral position in line with the pivot 18 when "thebottom of the model is in contact with the model wheel, thus reproducingthe bottom exactly; and to cfiect' all the magnification required abovethe bottom;

The model wheel susgension and the mechanism for keeping the model wheelcenter the grading plane (the plane passing tlmough the axis of rotationlla-n-d the neutral position of the center of the model wheel 54) issubstantially like that shown in my application Serial No. 530,214. Themodel wheel 54: is pivoted on an extension .56 making an angle "of about30 with astub shaft indicated also by the refeiience numerali52, Fig 2,on Whichthe extension is mounted. The model: wheel center 52 lies at theintersection of the axis of the stub shaft and the extension. The stubshaftzis-mounted in the enclof a lever 5.8 pivoted at 60 on the modelwheel slide 2d,:and hasa era-n l; arm 62 connected by a link 6 with themodel wheel slide. Tliestructure 6O,=V58, 56, 62,64

forms a parallelogram. This arrangement keeps the extension on the stubshaftfrom rotating in space as the lever 58 turns, can" ing the modelwheel witl it, so that the axis of the model wheel always remainsparallel to itself and consequently in the same angular relation to thegrading plane (passing through the model and work axes and the cuttercenter) and the correspondingly oriented cutter axis. This relation isnecessary in order to preserve similarity of conditions on the model andwork sides of the machine.

The rear arm of the lever 58 carries a pivoted slide block 66 Working ina slideway 68 fastened to a crankarm 70 mounted on the model wheelcarriage '33, and connected to the f anboard 16 by alink 2. As explainedin my application Serial No. 5230,21 tl is structure will cause themodel wheel center to remain always in the grading plane, following theaxis 13 the swing frame 10 oscillates, thus to preserve the similarityof conditions above referred to.

The model 14 is driven by a chaincf gearin'g beginning at a shaft 74having a long pinion 7 6 on it which drives the gear 50, as this gear iscarried along by themedel wheel carriage A gear 78 tne shaft 7 4 drivesa train of gears 80, 82, 84 the last being concentric with the shaft 12.The gear all drives integral gears '86 and 88, mounted on the swingframe 1 0, and the gear 88 drives a gear 90, having. ust twice as manyteeth and n'rounted on the model axis 13. It is shown in my applicationSerial No. 530,214 that this structure will keep any radial plane of themodel in the grading plane irrespectii "eof swing frame rotation, andthus preserve the proper reverse relation between the model and Worksides of the machine when the model and work (are rotated in oppositedirections in so-called reverse cutting.

All of the structure so far described'suhstantlly identical withstructuredescribed in my applications Serial No. 530,214 and Serial No.l-29,2 19, to which reference may be made for details not heremention-ed;

At each end of the .i'nachine are mounted a pair of standards 92, at then pe-r ends of which is mounted a downw. ll swing frame=9-l sin in alloth the swing frame 10,-and arranger to a second model 96. i shown, thismodel is mounted in a position rotated 480 from the positionof the model14;. A standar-" 98 mounted on the model wheel slide car a bell cran-khaving two arms 10), 10% will pivot 102 directly ahovethe pivot (30. Thehorizontal .a-rm 10sof the crank carries model wheel 106 which is mou tl o in just the same way-as the model wheel on the front end of thelever 58. The cram; arm 1G8 corresponds to the crank and the link 1'10,connecting the arm 1Q8-to the sta nd-ard 98*, corresponds to the linketer of the model.

The crank arm 100- is geared to-an equal crank arm 112 mountedat'60on'the lever 58. Thus, the two :model wheel Suspensions are identical.gearing exactly like that described for the rection and at the samespeed, by virtue of a shaft 114 and appropriate gearing connect ing theupper gearing to the shaft 74. er. The two swing frames are connected tothe fanboard 16 as follows. The swing frames are connected to each otherby a link 116 pivoted to the lower frame at 118, and pivoted at 120 toone end of a short link 122 pivoted at its other end to the upper frame,thus permitting the frames to swing freely. The center of the link116'is linked to the upper end of a rock-lever 124 by a link126 and thelower end of the rocklever is linked 39 to the fanboard by a link 128.Thus the movement of the link 128 and consequently of the fanboard isthe average of the movements of the two swing frames which are easilyseen to be proportional respectively to the two radii in contact withthe two model wheels. Owing to'the 1809 difference in the positions ofthe models these two radii, taken together, form the same diameter ofthe models 14, 96. Thus, the accret-ion at any point of the block isequal to the accretion factor multiplied by half the correspondingdiameter of the model, instead of the radius to the point in question,or by the mean of the two corresponding radii forming this diam- By theaccretion factor is meant the grading or magnification factor minusunity, taken algebraically. That is, if the block is, larger than themodel, the grading factor is 1.10 and the accretion factor is1.101.00=0.10; and if the block is v10% smaller than the model, thegrading factor is 0.90 and the accretion factor is 0.901.00= 0.10.

Therefore, the grading action at any point is based on the length of thediameter extending to that point, instead of merely the radius extendingto that point, so that if the bottom radii for example are to bereproduced unchanged they still have an efiect in to the grading of theupper part of themodel, and it is therefore unnecessary to adopt such anextreme grading factor for the top as would be necessary if only theupper radii were available there for magnification.

V The contact of the two model'wheels 54, 106 with geometricallyopposite sides of the identical models 14, 96'amounts in effect tocalipering the corresponding diameter or measuring the two correspondingopposed (i0 radii of either one of the models, and this diameter ismultiplied by one-halfthe glradning fa gtgr then being utilized in themac ine.

The two models may--be said to Joe-engaged by the model wheels. onopposite sides of their (identical) model figure, by which isv meant Themodel 9.6 is driven by.

model 14, the rotation being in the same ditive of its swing-framerotation,

-:' The gear 50,

opposite sides of the models considered as recognizable geometricalshapes, irrespective of their positions in space. Each model wheelremains in its own grading plane by virtue of the connection 100- 112,and any diametral plane of each model which is in its grading planeremains in its grading plane irrespecby virtue of the drive gearingdescribed.

same angular velocity as the models, and. by

proper design of the cam 48 any desired cycle of setting of the feelerroll .20 on the fanboard 16 can be obtained, as described'in myapplication Serial No. 530,214.

The mountin'gof theblock 15, the construction of the cutter 132 and thedrive of the model wheel and cutter carriages are all as described in myapplication Serial No. 530,214 v Having described my invention, what Iclaim as new and desire to secure by Letters Patent of the United Statesis:

1. In a pattern copying machine, means for holding a block and a model,a tool, and a,

width grading mechanism arranged to co-op" erate with the model, thewidth grading mechanism. being constructed and arranged to grade from offrom a radius comprised in the diameter.

2 In a pattern copying machine, means for holding a block and a model, atool, and a width grading mechanismarranged to co-operate with themodel, the width gradingmechanism being constructed and arranged tocaliper the diameter of the model and to mule tipl'y it by amagnification factor in the block.

3. In apattern copyingmachine', means-for as stated, is rotated at the adiameter of the model instead holding a block and a'model, a tool, and awidth grading mechanism arranged to, co-operate with the model, thewidth grading mechanism being constructedand arranged to measure twooppositely'extending radiiof the model and to magnifytheir sum in thework. 7

4. In a pattern copymg machine, means for holdinga block and. a model,a-tool,and a width grading mechanism arranged to co-operate with themodel, the width grading mechanism being constructed and arranged tomeasure two oppositely extending radii of the model and to multiplytheir mean by the width grading factor.

5. In a pattern copymgmachine, means for holding a block and a model, atool, and a width grading mechanism arranged to co-operate with themodel, the width grading mechanism being constructed and arranged tomeasure two oppositely extending radii of the model and to addalgebraically to the block radius then on the cutter aquantity dependingupon the mean of'the two said oppositely extending model radii.

6. In apattern copying machine, means for holding ablock and a model, atool, and a width'grading mechanism arranged to co;op- 3.-

crate with the model, the widthgradin'g mech anism being constructed andarranged to measure two oppositely extending radiiof the model and toadd algebraically to the block radius then on the cutter a quantitydepending upon the sum of the two said oppositely extending model radii.

7. In a pattern -copying machine, means for holding a block and a model,a tool, and a width grading mechanism arranged to'co-opcrate with themodel, the width grading mechanism being constructed and arranged tomeasure two oppositely extending radii of the model and toadd,,-al-gebraically to each of the corresponding block radii a quantityequal to the product of the mean of the said model radii by theaccretion factor.

8. In a pattern'copying machine, means'fo-r holding a block and a model,a tool, and a Width grading mechanism arranged to :co-opcrate with themodel, the width grading mechanism beiin g constructed and arranged tomeasure two oppositely extending radii of themed-e1 and to addalgebraically, at laterally opposite points of the block, to the modelradius being graded, a quantity equal to the producto'f the mea'n'of themodel radius being graded and its opposed radius by the accreti'onfactor. n

9;. A width grading mechanism for a copying lathe comprising a gradingslide and two "model wheels,and means formovin g the slide controlledbythe contact-of the model wheels with-two opposed model radii. I 10. Awidth-grading mechanism for acopyinglath'e comprising a model holdingmeans,

a grading slide carrying two model wheels arranged for movement towardand from the model holding means, and means for moving the slidecontrolled by contact of the model wheels with the ends of opposed modelradii.

11. A copying lathe having two oscillating names, model holding means ineach frame, 'two'model wheels arranged to contact with opposite sides ofthe model figure of the models in the model holding means, respectively,and a grading slide gc iverned by the oscillating frames.

12. A copying lathe'having two oscillating frames, model holding meansin each frame, two model wheels arranged to contact with opposite sidesof the model figure of the models in the model holding means,respectively, a grading slide, a control therefor, and a' connectionbetween each oscillating frame and the grading slide control.

13. A copying lathe having two oscillating frames, model holding meansin each frame, two model wheels arranged to contact withgeometricallyopposite sides of models in the model holding means,respectively, a grading slide, a link connecting the oscillating frames,and a connection between the grading slide and a mid point .of the link14. A copying lathe having two'oscillating frames, model holding meansin each frame, two model wheels arranged to contact with models in themodel holding means on opposite sides, respectively, of the model figuredefined by said models, a grading slide, a link connecting theoscillating frames, and a conpecipion between the grading slide and the15. A copying lathe having two oscillating frames, model holding meansin each frame, two model wheels arranged to contact with models in themodel holding means on opposite sides, respectively, of the model figuredefined by said models, a grading slide, a fanboard to operate thegrading slide, and a connection running from the fanboard to bothoscillating frames.

16. A copying lathe having two oscillating frames, model holding meansin each frame, two model wheels arranged to contact with geometricallyopposite sides of models in the model holding means, respectively, alink connecting the oscillating frames, grading slide, a fanboard tooperate the grading slide, and a connection running from the fanboard tothe link.

17. A copying lathe having two oscillating frames, model holding meansin each frame, two model wheels arranged to contact with models in themodel holding means, substantially respectively, on opposite ends ofcorresponding diameters thereof, a link connecting the oscillatingframes, a grading slide, a

fanboard to operate the grading slide, and a connection running from thefanboard to the center of the link.

18. A copying lathe having two oscillating frames, model holding meansin each frame, two model wheels arranged to contact with models in themodel holding means, substantially respectively, on opposite ends ofcorresponding diameters thereof, a grading slide, a fanboard, anadjustable feeler extending from the grading slide to the fanboard, a

connection between the fanboard and both oscillating frames, and meansfor automatic'ally altering the adjustment of the feeler during theproduction of a work piece.

19. A copying lathe having two frames, model holding means in eachframe, two model wheels arranged to contact with models in the modelholding means, substantially respectively, on opposite ends ofcorresponding diameters thereof, a grading slide, a fanboard, anadjustable feeler extending from the grading slide to the fanboard, aconnection between the fanboard and both oscillating frames, and meansfor automatically altering the adjustment of the feeler during theproduction of a work piece, said last-mentioned means operating in acycle having the same time length as a rotation of a model.

20. In a pattern copying machine, means for holding a block and a model,a tool, a

oscillating 1.1.

not of half the corresponding model diameter width grading mechanismarranged to cooperate with the model, the width grading mechanism beingconstructed and arranged to grade from a diameter of the model insteadof from a radius thereof, and means for automatically alterin thegrading factor during the production 0 a work piece.

21. That improvement in methods of pattern copying which consists inwidth grading from a diameter of the model instead of from a radiuscomprised in the diameter.

22. That improvement in methods of pattern copying which consists inmeasuring a diameter of the model instead of a radius comprised in thediameter and determining a point in the surface of the work by adding tothe corresponding model radius the prodby the accretion factor.

23. That improvement in methods of pattern copying which consists inmeasuring two opposed model radii and determining a point on the surfaceof the work corresponding to the end of one of the said model radii byadding to the said corresponding model radius the product of the mean ofthe two said model radii by the accretion factor.

24. That improvement in methods of pattern copying which consists inmeasuring two opposed model radii and determining two opposed points onthe surface of the work corresponding to the ends of the said modelradii by adding to each of the said corresponding radii half the productof the sum of the said model radii by the accretion factor. V

In testimony whereof I have signed my name to this specification.

' LAURENCE E. TOPHAM.

